Objective To investigate the quality of life and its influencing factors of families primary caregivers of dementia patients .Methods The typically self made questionnaire ,WHO quality of life measurement profile (WHOQOL‐BREF) ,zarit bur‐den of care scale(ZBI) ,social support rating scale (SSRS) et al were adopted to investigate 64 caregivers of AD patients .Results (1) The overall quality of life of family caregivers of total subjective feelings were significantly lower than the general health status of subjective feeling score (t= -2 .217 ,P=0 .030) .The field of physiological and psychology points have no statistically significant difference in comparison with Chinese norm (t= -0 .252 ,-1 .994 ,P=0 .801 ,0 .050);the field of social and environment points have statistically significant difference compared with norm(t= -3 .830 ,3 .658 ,P=0 .000 ,0 .001) .(2) caregiver who have spouse , poor parent child relationship and patients with somatic diseases and mental behavior symptoms have lower quality of life(P<0 .05) .(3)Total score of Quality of life was negatively associated with total score of care burden (r= -0 .433 ,P=0 .000) ,while was significant positive associated with total score of the social support (r=0 .346 ,P=0 .005) .(4)Marital status ,parent‐child rela‐tionship ,physical illness and social support were the main factors affecting the quality of life(r2 =0 .409) .Conclusion Strengthen the social support and psychological intervention of dementia caregivers who has a spouse ,poor parent-child relationship and poor physical condition may help to improve the quality of life .